Devices for capturing and storing bodily fluid intravaginally are commercially available and known in the literature. Intravaginal tampons are the most common example of such devices. Commercially available tampons are generally compressed cylindrical masses of absorbent fibers that may be over-wrapped with an absorbent or nonabsorbent cover layer.
The tampon is inserted into the human vagina and retained there for a time for the purpose of capturing and storing intravaginal bodily fluids, most commonly menstrual fluid. As intravaginal bodily fluid contacts the tampon, it should be absorbed and retained by the absorbent material of the tampon. After a time, the tampon and its retained fluid is removed and disposed, and if necessary, another tampon is inserted.
There are many brands of tampons commercially available. In general, tampons are split into two categories, those contained and delivered into the body by an applicator and those which are digitally inserted. The tampon of the present invention may be utilized by both delivery means although it is especially appropriate for it to be digitally inserted.
In particular, the tampon of the present invention is formed by processes and apparatus as described in U.S. Pat. No. 6,310,269 (Friese et al.) and U.S. Pat. No. 5,832,576 (Leutwyler et al.). The tampons formed by these processes have center cores which are highly compressed, resulting in densified cores having sufficient column strength required for digital insertion. The area surrounding the core is less dense and has inwardly open grooves, which increase the circumferential surface area of the tampon. The grooves may be straight and aligned parallel to the longitudinal axis or may be of an at least partially helical nature as disclosed in EP 1383453 (Schoelling). In this patent, the shaped, pressed longitudinal grooves increase the surface area, increase the distance the body fluid has to travel and increase the dwell time of the liquid in the at least partially helical grooves. This allows for better absorption and expansion capacity of the tampon than longitudinal, straight grooves.
Other examples of grooves may be found in US Pat. Pub. 2008/0200892, EP 1481656 and WO 2008/095937 (all to Van Ingelgem et al.), EP 1459720 (Schmidt), and US Pat. Pub. 20070083182 (Schoelling). Additionally, tampons having recessed portions such as those in US Pat. Pubs. 20050113784, 20050113785, and 20050113789 (all to Jensen). These recessed portions may be arranged in patterns such as diagonal lines, straight lines, checkerboard and mixtures thereof.
While the invention of helical or other non-linear grooves has increased the absorption of fluid and helped prevent tampon failure, there still remains a need to direct fluid over the outer surface of the tampon. Too often, tampons fail without becoming saturated. This is especially evident when the user removes the tampon and only one side of the tampon has expanded due to fluid absorption.